1. Field of the Invention
The present invention relates to a composition suitable for simulating and evaluating chemical agent contamination. More particularly, the invention provides compositions which can be used to safely train military personnel in handling chemical agent decontamination.
2. Description of the Prior Art
The handling of chemical agent contamination is an important part of military training. The exposure of military personnel even to small amounts of real contaminants, i.e. nerve and/or blistering agents is impractical due to the risk of injury involved. There is therefore a need to use a relatively harmless composition which simulates the effects of such chemical agent contaminants without injuring trainees. The invention therefore provides a chemical agent simulant composition for operational evaluation of chemical agent contamination. It is useful for providing a measure of the extent of contamination from spills or dispersion devices, and the effectiveness of decontamination procedures. The inventive composition employs a unique combination of compatible detection materials which are environmentally safe and incorporate simulated vapor signature components, as well as a liquid fluorescence signature component. It provides a simulant chemical agent vapor signature for chemical detection systems, as well as a visible indicator of liquid contamination when irradiated with an ultraviolet light source. This system can be useful for determination of the extent of aerosol or droplet depositions as well. Certain compositions of this system can also be detected using military chemical agent detection papers such as the U.S. Military's M8 or M9 detection papers. These papers utilize specific dye chemistries that also could be utilized to detect various levels of liquid droplet contamination.
The invention provides a relatively safe and environmentally friendly training aid for liquid G-agent (i.e., nerve agent, including VX) and H-agent (mustard-HD) simulants having varying viscosity. A preferred G agent simulant according to the invention would be a liquid mixture of dipropylene glycol monomethyl ether (DPGME), a fluorescent dye and a solvent such as polyethylene glycol (PEG-200) or water. The H-agent simulant is a liquid mixture of methyl salicylate (MS), a fluorescent dye and a solvent. DPGME, MS, and PEG-200 all have each been used individually and in certain combination for years as chemical agent simulants. The ion mobility characteristics of the functional groups associated with DPGME and MS lends itself well for detectability using ion mobility spectrometers (i.e. the Chemical Agent Monitor (CAM)). In addition, MS and DPGME vapors can be detected by infrared, surface acoustic wave (SAW) and several other detection or monitoring technologies. DPGME and MS have been applied to random test personnel, equipment and vehicles, so the CAM could be operationally used to sort contaminated from clean personnel or materiel. Fluorescent brightening agents have been added as a fluorescence tracer to PEG-200 to see how well the simulant was applied to contaminated test vehicles. M8 or M9 detection papers can also be used to verify gross liquid or droplet contamination.
The prior art to date has not produced a G or H chemical agent training simulant having the combined attributes of being a relatively innocuous material, good simulant agent liquid and vapor property correlation, a visual confirmation using a fluorescent whitening agent to show the extent of liquid contamination present, vapor signature detection by several technologies, and an actual chemical reaction simulating neutralization occurring between the training chemical agent simulant and an actual applied decontamination solution. At present, only the physical removal of decontamination procedures (i.e., soap & water, scrub brushes) can be evaluated. Therefore, present decontamination training operations using chemical agent simulants can only evaluate the mechanical process of contamination removal. Training with the present composition would simulate both the chemical neutralization and physical removal of the contamination. This system would provide a much better method for contamination assessment and decontamination effectiveness, to be used in training of military and hazardous materials responders.
The invention provides relatively safe, environmentally friendly (i.e., non-listed Resource Conservation Recovery Act (RCRA)) chemical mixtures that can be used to demonstrate a G or H agent liquid or vapor behavior and simulate the neutralization reaction which occurs when the simulant is exposed to a decontamination solution. The fluorescent tracer added to the simulants allows a visual confirmation of contamination present before and after decontamination procedures with the use of an UV lamp. The chemical agent simulants can be thickened in various degrees by adding a thickening agent such as polymethyl methacrylate polymer in order to achieve the desired liquid or liquid mixture viscosity.